Various forms of irrigation systems using laterally advanceable overhead horizontal water conduits are provided with large amounts of water under high pressure and the conduits include spray heads spaced therealong from which the water within the conduits may be sprayed for irrigation purposes. These types of irrigation systems require the use of high power consuming pumps inasmuch as a large volume of water must be provided and the water within the conduit must be maintained at relatively high pressures in order to enable the spray heads supported therefrom to discharge water considerable distances. In order to provide sufficient power to drive the high volume and high pressure pumps required in irrigation systems of this type, high powered diesel engines are often utilized as motive sources. However, the increased cost of diesel fuel and manufacturing and maintenance costs associated with diesel engines has in recent years made the cost of irrigating crops too expensive for all but the larger farms. Accordingly, a need exists for a less expensive means of irrigating crops through the utilization of mobile irrigation systems.
Therefore, there is disclosed hereinafter a mobile irrigation system to which a large volume of water is provided under low pressure and each spray head location of the irrigation system utilizes an electric motor driven horizontal disc upon the center portion of which irrigation water is discharged and the disc includes upwardly projecting and generally radially extending slinger-type vanes whereby the motive force to project water from each spray head is obtained directly from the associated electric motor. In this manner, relatively inexpensive electric power may be utilized to effect the spray discharge water over relatively great distances.
Examples of slinger-type liquid discharge devices including some of the general structural and operational features of the instant invention are disclosed in U.S. Pat. Nos. 2,756,100, 2,939,636, 2,945,627, 2,994,482, 3,288,052 and 3,934,812.